Electrotechnologies save on capital investment, installation, and operation relative to applications fueled by other energy sources. At the same time a significant advantage is realized in that electrotechnologies provide for a cleaner environment. One example of efficient new electrotechnologies is the electric vehicle recently introduced by automobile manufacturers.
The present generation electric vehicles are designed as second cars or for those who primarily drive around town or commute short distances. A current generation electric vehicle carries 1175 pounds of lead-acid batteries. In these current generation electric vehicles, a single charge, which takes several hours to complete, will provide enough power for about four hours of city driving. According to General Motors, the electric vehicles with lead-acid batteries get about 70 miles of city driving or 90 miles of highway driving on 85 percent of a battery charge.
These figures, however, were measured in the laboratory with an electric car driving on a chassis dynamometer according to a test schedule invented by the Environmental Protection Agency to measure an average car's fuel economy. In tests involving actual real life highway scenarios including winds, grades, and traffic, the electric cars actually produce a reported range of approximately 65 miles on a single charge. Thus, electric cars currently have an actual range that is less than the round-trip commute that millions of metropolitan area residents endure every day.
Power consumption in an electric vehicle is affected by terrain grades, traffic conditions or number of stops, how hard the car is driven, wind, temperature, vehicle weight, number of batteries, and type of batteries. Power consumption is also affected by the state of the other electrical equipment in the vehicle, for instance the windshield wipers, air conditioning, stereo or radio, and lights. When the electric vehicle batteries have lost 70 percent of their power, battery output is automatically reduced to conserve the remaining energy, and the car drives substantially more slowly until the batteries have been recharged, typically by "plugging" the car into an electric outlet. Because of the relatively short range of the current generation electric vehicles, a conservative driving style is required. This conservative driving style comprises precise accelerations and slow, coasting stops, aimed at saving power. With better batteries and a realistic infrastructure to replenish them, electric cars could be a sensible alternative to the car powered by an internal combustion engine.
In addition to the significant reduction in pollution, another advantage of the electric vehicle is that the cost of running the vehicle is low. The average current generation electric vehicle with lead-acid batteries charged at the current average grid power rate would have a fuel cost that is 15% of the cost of powering the same vehicle with an internal combustion engine. However, when an electric vehicle is fully charged it has the equivalent energy of only about a gallon and a half of gasoline on board. Therefore, battery technology has resulted in a long wait for an effective electric car because few drivers want to lumber around town in a vehicle with a very short range weighed down with over half a ton of lead-acid batteries. While the range of the current generation electric vehicles can be increased with frequent chargings, there is currently no infrastructure to support charging these vehicles while away from one's home.
While Americans like driving long distances which the current generation of electric cars cannot support, electric vehicles are a certainty because of the zero-emission requirements that take effect in some states in the very near future. Consequently, a concentrated effort is being made by domestic and foreign automobile manufacturers and governments to make electric vehicles more appealing. As a result of this effort, several solutions are being pursued to the battery life problem of the current generation electric vehicle.
One solution which is currently being undertaken is a planned network of high power charging stations. These stations will be installed across the country and will allow drivers to quickly recharge the electric vehicle batteries, thereby allowing drivers to travel farther without running out of power. The major disadvantage to this solution is that is requires the development of a new infrastructure at a significant cost with regards to time and money.
Automobile manufacturers have also been experimenting with cars powered by a compact fuel cell that converts gasoline to hydrogen, which then powers an electric motor. This propulsion package fits into a normal-size car and promises approximately 80 miles per gallon and a range of about 500 miles. While a 500 mile range is an improvement over the current generation electric vehicle, it is still a limit which few drivers might tolerate because of the high cost of the vehicle.
Automobile manufacturers are also experimenting with various hybrid solutions such as a vehicle that has an electric motor for city use and a diesel engine for the highway. The hybrid vehicle solves the fundamental problem which has plagued electric vehicles from the start, the restricted range and the lengthy period normally needed to recharge batteries. In a hybrid vehicle, an internal combustion engine is used to provide acceptable highway performance while simultaneously recharging the electrical power system's batteries. In urban areas where exhaust pollution is a contentious issue, the vehicle will run on battery power alone. A variant of the hybrid vehicle uses a much smaller internal combustion engine running at a constant speed to keep the batteries charged. However, the hybrid vehicle does pollute the environment when running on the petroleum engine.
Automobile manufacturers are investing huge amounts in battery development. The new nickel-metal hydride and lithium-ion batteries can provide double the distance of lead-acid varieties. A zinc-air battery may also be available which is reputed to double the range of an electric vehicle for the same weight. Electric cars with lead-acid batteries can reach speeds of up to 60 miles per hour and travel a mean maximum distance of approximately 60 miles on a single charge. While still providing a significant range restriction, the new generation batteries stretch this to about 80 miles per hour and a mean maximum distance of about 125 miles on a single charge.
The superbatteries needed to give electric vehicles viable range are still a long way technologically. The other most promising long-term technology, the hydrogen fuel cell, is also a long way technologically. Therefore, the hybrid is acknowledged industry-wide as the nearest thing to a technological answer, and it still does not provide the best protection for the environment. Consequently, there is a need for a battery charging device that will significantly increase the range of the electric vehicle while reducing the period needed to recharge the batteries of an electric vehicle, thereby completely eliminating the hybrid vehicle requirement for an internal combustion engine.